Descriptions of individuals showing symptoms consistent with Obsessive Compulsive Disorder are present in texts dating back many centuries. Psychoanalysts considered such symptoms to be a prominent demonstration of dynamic forces at play, with compulsions a defense against anxiety-provoking impulses. Such formulations were a strong influence on the original DSM classification of OCD as a neurotic (later anxiety) disorder. Later editions have removed such aetiological considerations, but retained the classification of OCD. Moving towards the DSM-V, a number of issues are being revisited, including whether symptom subgroups are both defmable and useful, whether compulsive hoarding should be considered a subtype of OCD, and whether OCD should continue to be considered an anxiety disorder, or whether it should be reclassified as an Obsessive-Compulsive spectrum disorder along with disorders with similar symptomatology or aetiology. This chapter briefly reviews the arguments being made on these issues, and also considers cultural influences on the presentation and diagnosis of OCD.